The present invention relates in general to sources of electrons, and in particular, to an electron beam source.
Electron beams can be used to sterilize medical instruments, food and packaging. Irradiation by electrons is an accepted medical treatment for certain skin cancers. Environmental uses are cleaning flue gasses and decontamination of medical waste. Industrial applications are drying of inks and polymer crosslinking.
Referring to FIG. 1, an electron source 100 generally consists of a hot filament 101 maintained at high voltage inside of a vacuum tube 102 and an exit window 103. Because the window 103 is a fragile, thin foil, it must be somewhat small in size so that it does not tear under air pressure present due to the vacuum in the tube 102.